title: Screening for Down's syndrome: the effect of test date on the detection rate.
abstract: Screening tests for Down's syndrome are carried out at different gestational ages. Because of fetal loss, crude estimates of their detection rates cannot be directly compared. We present methods for estimating the true detection rates along with their standard errors. This enables a proper statistical comparison of the true detection rates of tests carried out, for example, in different trimesters.
authors.affiliation: Department of Medical Computing & Statistics, University of Wales College of Medicine, Cardiff, UK.
authors.forename: F D
authors.initials: FD
authors.lastname: Dunstan
authors.forename: A B
authors.initials: AB
authors.lastname: Nix
mesh_terms: D004314:Down Syndrome / Q000175:diagnosis*; D005260:Female; D005865:Gestational Age; D006801:Humans; D008403:Mass Screening / Q000379:methods*; D011237:Predictive Value of Tests; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D013223:Statistics as Topic